1. Field of the Invention
The present invention relates to an evaluation method and an exposure apparatus.
2. Description of the Related Art
In the conventional projection exposure apparatus, the optical performance of a projection optical system, such as a focus, a distortion, and other aberrations, is evaluated based on an exposure result that is obtained by utilizing an actually exposed original. However, as the original becomes larger and the exposure performance deteriorates due to a self-weight deformation of the original, it is difficult to determine whether any error in the exposure result attributes to the projection optical system or the original. Accordingly, Japanese Patent Laid-Open No. (“JP”) 10-92718 proposes to form a press chamber on one surface side of the original, and to correct the deformation of the original by adjusting the pressure in the press chamber. JP 10-214780 proposes a correction through a focus control of the projection optical system.
Other prior art include International Publication No. WO03/088329.
As the original becomes larger, it becomes difficult to remove the self-weight deformation of the original only through the correction mechanism proposed in JP 10-92718. In addition, as the original becomes larger, influence of an uneven thickness or a patterning error amount of the original upon the resolving performance becomes non-negligible. Moreover, as in JP 10-214780, when an error of the original is converted into an error of the projection optical system, a highly precise correction cannot be performed.